Gymnodimine, pinnatoxin, prorocentrolide, and spirolide are marine toxins with potent biological activity. These marine toxins pose a serious threat to the public health. These natural products all contain an unusual cyclic amine adjacent to a quaternary center and contain a large macrocyle. By exploiting the proper conformational restrictions, an intramolecular Alder reaction may be applied to achieve the synthesis of these structural element s in a stereo selective manner. A cis-2,5-disubstituted furan will be synthesized in a series of stereo selective reactions. Convergent assembly of a molecule that contains a diene and a dienophile by using to Nozaki- Kishi couplings will be preformed An intramolecular Diels-Alder reaction will be used to form a macrocyle that will be converted into gymnodimine.